Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description adds real value beyond that: it names the underlying endpoint (GET /units/{id}), discloses that text fields are 'clipped' (truncated) and explicitly excludes images and owner data, which tells the agent not to expect those fields.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

One front-loaded sentence plus the endpoint, no filler. The most decision-relevant information (single object, keyed by id, what comes back, what is missing) is packed into the first clause.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the description carries the burden of describing returns and it does so by enumerating fields and naming exclusions, plus the truncation caveat. Only minor gaps remain, such as behavior on an unknown or unauthorized id.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100% for the single required property_id, so the schema already documents format and bounds (integer > 0). The description only restates 'by id' without adding syntax, error or resolution behavior, so the baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ('One property (Objekt) by id') and enumerates the returned facets (address, type, rooms, areas, prices, status, texts). The word 'One' plus the id keying distinguishes it clearly from the sibling propstack_list_properties without needing to open a schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Usage is only implied: an agent can infer this is the single-object lookup keyed by id versus the list endpoint, but the description never states when to prefer it over propstack_list_properties or what to do when the id is unknown. No prerequisites or exclusions are given.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.